Update README.md

This update is to make sure our users are aware that we are constantly keeping things fresh and are always keeping an eye on the calculator in order to make sure that there are no issues as well as to introduce new features.

Author: Ishtiyaqhalim

README.md

@@ -13,4 +13,4 @@ Output
    simple interest = p*t*r
 ```
 
-_© 2022 XYZ, Inc._
+_© 2023 XYZ, Inc._